From fae50bd72c817f53546e4d07623c612c09a0094e Mon Sep 17 00:00:00 2001
From: Yang Jun <harttleharttle@gmail.com>
Date: Sun, 10 May 2026 15:23:01 +0800
Subject: [PATCH] refactor(strip_html): inline block kinds to match file style

Drop the module-level STRIP_BLOCKS table; the rest of the file keeps
each filter self-contained (only escapeMap/unescapeMap are top-level
maps shared across filters). Two openers don't justify a table.

Co-authored-by: Cursor <cursoragent@cursor.com>
---
 src/filters/html.ts | 26 +++++++++++---------------
 1 file changed, 11 insertions(+), 15 deletions(-)

diff --git a/src/filters/html.ts b/src/filters/html.ts
index 90a83f096..c44ef92da 100644
--- a/src/filters/html.ts
+++ b/src/filters/html.ts
@@ -42,32 +42,28 @@ export function newline_to_br (this: FilterImpl, v: string) {
   return str.replace(/\r?\n/gm, '<br />\n')
 }
 
-// Linear-time replacement for the previous backtracking regex
+// Linear-time strip via indexOf scan. A regex equivalent to the old
 //   /<script[\s\S]*?<\/script>|<style[\s\S]*?<\/style>|<[\s\S]*?>|<!--[\s\S]*?-->/g
-// which is O(n^2) in V8 on inputs with many unclosed openers. JS regex has no atomic
-// groups / possessive quantifiers, so unrolled-loop patterns don't help asymptotically.
-// We scan forward with indexOf and cache the next known closer per kind so unclosed
-// openers don't re-scan the tail. Each character is visited O(1) times.
-const STRIP_BLOCKS = [['<script', '</script>'], ['<style', '</style>']] as const
-
+// is O(n^2) on unclosed openers (JS regex has no atomic groups / memoization),
+// so we cache "next known </script>/</style> position" across openers.
 export function strip_html (this: FilterImpl, v: string) {
   const str = stringify(v)
   this.context.memoryLimit.use(str.length)
-  const closers = [0, 0]
   let out = ''
   let i = 0
+  let scriptEnd = 0
+  let styleEnd = 0
   while (i < str.length) {
     const lt = str.indexOf('<', i)
     if (lt < 0) return out + str.slice(i)
     out += str.slice(i, lt)
     let end = -1
-    for (let k = 0; k < STRIP_BLOCKS.length; k++) {
-      const [opener, closer] = STRIP_BLOCKS[k]
-      if (!str.startsWith(opener, lt)) continue
-      const from = lt + opener.length
-      if (closers[k] !== -1 && closers[k] < from) closers[k] = str.indexOf(closer, from)
-      if (closers[k] >= 0) end = closers[k] + closer.length
-      break
+    if (str.startsWith('<script', lt)) {
+      if (scriptEnd >= 0 && scriptEnd < lt + 7) scriptEnd = str.indexOf('</script>', lt + 7)
+      if (scriptEnd >= 0) end = scriptEnd + 9
+    } else if (str.startsWith('<style', lt)) {
+      if (styleEnd >= 0 && styleEnd < lt + 6) styleEnd = str.indexOf('</style>', lt + 6)
+      if (styleEnd >= 0) end = styleEnd + 8
     }
     if (end < 0) end = str.indexOf('>', lt + 1) + 1
     if (end <= 0) return out + str.slice(lt)